Influence of Toughness and Retained Austenite on Wear Behaviour of Carbide-Free Bainite in High Silicon Steel

The goal of the current work was to investigate several heat treatment techniques to produce carbide-free bainite (CFB) in high silicon spring steel. Because silicon prevents the formation of carbide precipitation during austempering, it aids in the development of carbide-free bainite (steel compositions are 0.551%C, 1.756%Si, 0.825%Mn, and 0.13%Cr). Heat treatment at varying austempering temperatures of 300 °C, 350 °C, and 400 °C with holding times of 10, 20, and 30 min has been used to give treated samples the desired microstructure. Additionally, the disc-on-disc testing apparatus has been used to analyse the wear rates of the base and treated samples. The percentage of retained austenite in the carbon helps to prevent crack initiation and spread by undergoing transformation during deformation. It also increases the treated sample's wear resistance and toughness. It has been thoroughly investigated how hardness and the fraction of retained austenite affect the particular wear rate. X-ray diffraction and scanning electron microscopy have been used to critically analyse the phase fraction and preserve austenite stability. CFB steel has a toughness range of 27 ± 0.8–70 ± 1.0.